Objective.To create and validate an instrument that identifies women's vulnerability to domestic violence through gender subordination indicators in the family. Methods. An instrument consisting on 61 phrases was created, that indicates gender subordination in the family. After the assessment from ten judges, 34 phrases were validated. The approved version was administered to 321 health service users of São José dos Pinhais (Estado de Paraná, Brasil), along with the validated Portuguese version of the Abuse Assessment Screen (AAS) (for purposes of separating the sample group - the ''YES'' group was composed of women who have suffered violence and the ''NO'' group consisted of women who had not suffered violence). Data were transferred into the Statistical Package for the Social Sciences (SPSS) software, version 22, and quantitatively analyzed using exploratory and factor analysis, and tests for internal consistency. Results. After analysis (Kaiser-Meyer-Olkin (KMO) statistics, Monte Carlo Principal Components Analysis (PCA, and diagram segmentation), two factors were identified: F1 - consisting of phrases related to home maintenance and family structure; F2 - phrases intrinsic to the couple's relationship. For the statements that reinforce gender subordination, the mean of the factors were higher for the group that answered YES to one of the violence identifying issues. Conclusions. The created instrument was able to identify women who were vulnerable to domestic violence using gender subordination indicators. This could be an important tool for nurses and other professionals in multidisciplinary teams, in order to organize and plan actions to prevent violence against women.

Violence is a health problem that affects society, causing deaths, injuries, physical, emotional and spiritual trauma, and significantly interfering with quality of life. Regarding violence against women, high demand for health care in primary care services by female victims of gender violence have been indicated by studies.1-3 The primary health care in Brazil, within the model of the Family Health Strategy (FHS), provides a privileged space to identify the vulnerability of women to domestic violence, as it acts as a gateway to the health system, has locations that are widely scattered throughout the country, and offers conditions for nurses to establish a relationship with the client. Working on the perspective of vulnerability contributes to the renewal of public health and nursing practices to focus analysis on the collective plan, structured in an ethical-philosophical framework that seeks the critical interpretation of the data. This analytical perspective enlarges the horizons beyond the approach that is limited to individual responsibility, which is traditionally used.4 However, the lack of team preparation to deal with domestic violence, the difficulty for women to talk about the subject, and for professionals to ask them, and the technical and ethical limitations of care leave this vulnerability to violence hidden, and it is treated as if the complaints are of a biological nature.5

Violence against women appears in the health agenda because of the feminist movement, which pressured and continues to pressure the health sector, to be proactive and provide concrete answers, not only for the treatment of injuries and trauma from violence, but acting on the causes, by means of positive actions.6 Specifically related to violence against women, the Ministry of Health recognizes that social, economic and structural inequalities and policies between men and women, the rigid differentiation of roles, the ideas about virility linked to the male domain and honor are factors for the violence genre.7 Even with the improvements in quality of life in Brazil, serious gender inequalities that sustain the gender subordination are evident. The National Household Sample Survey of 2011revealed that women continued entering into the workforce outside the home, increasing their education level and having fewer children, however, the relationship between the female and male roles indicate differences in the integration into the labor market between men and women, expressed by differences in the rates of activity and unemployment. The level of employment in 2009 (percentage of employed persons in relation to the total persons) was 46.8% for women and 67.8%for men; the unemployment rate was 11.1% for women and 6.2% for men, and the distribution of the economically active population (EAP ) was 43.9% for women and 56.1% for men.8

Based on the assumption that the higher the subordination, more vulnerable the woman will be to domestic violence, the question arises: how do we identify vulnerability to domestic violence against women, anticipating the problem before a violent situation, in the form of aggression and death, leads to the need for health services, ? To answer the question, a study was conducted to develop and validate an instrument that identifies the vulnerability of women to family domestic violence by means of gender subordination indicators.

METHODOLOGY

The studies of the research group, ''Gender, health and nursing,'' of the School of Nursing, University of São Paulo, credentialed in the CNPq Research Groups Directory - Brazil - and whose scope produced the dissertation from which this article originated, deal with the concept of gender violence as a historical and social construction, resulting from the inequalities generated by differences in the construction of masculinity and femininity in the androcentric society in which we live. It extends the vision of the phenomenon to understand the determination of the process and its relationship with other phenomena, including, gender subordination in the family scenario. This was a methodological research study, focused on the development of instruments for data collection, in order to improve the reliability and validity of a tool,9 developed with the clients from the network of primary care services in the City of San Jose dos Pinhais, located in the State of Parana, Brazil. The project was analyzed and approved by the Research Ethics Committee, under protocol No. 00898212.6.0000.5392.

Creation and validation of the first version of the instrument

The results obtained by Okabe,10 were used for creating the instrument, based on the evaluation of indicators of (in)equality in the family, by Goldani,11 which found daily practices and representations of gender subordination in the family (Table 1).

From the reports of women who experienced situations of domestic violence, interviewed by Okabe,10 one or more thematic phrases were selected that could indicate the reiteration of the current hegemonic conception of gender subordination, or to overcome this concept. A questionnaire was developed on gender subordination in the family, with 61 phrases, comprising most of the indicators, and was evaluated by ten judges. Those judges were considered qualified to analyze the content, presentation, clarity and instrument comprehension in order to validate it. The questions contained in the instrument were evaluated by the judges and considered representative of the content of the domain to be measured. Content validity refers to the domain of a construct or universe that provides the basis for the formulation of questions fairly representing the content.12,13 For this research, the judges were chosen by convenience, taking into account the following criteria: professor in public or women's health, researcher in the area, or nurse providing care for women. The material was sent by email to the judges, asking for their opinion on: 1) whether the indicator phrase was illustrative of what it was supposed to mean, and if the reality experienced by a woman was explicitly described; 2) presentation, clarity and understanding of the phrase. There were 34 phrases in which the agreement between the judges was more than 80%, and thus were considered validated.

Preparation and validation of the second instrument

After validation by the judges, a second instrument was prepared to be tested with the women, to verify the relationship between gender subordination in the family and the occurrence of domestic violence, and it consisted of three parts: 1) identification of the respondents; 2) questionnaire for identifying the vulnerability for domestic violence due to gender subordination; 3) questionnaire about experience of situations of violence (validated Portuguese language version of the Abuse Assessment Screen - AAS).14 The responses on vulnerability to domestic violence by gender subordination were recorded on a Likert scale, ranging from 1 to 4. Before responding, the women received the following guidance: ''Answer: 1 - If this never happens to you, it has nothing to do with your life or with your thinking; 2 - It happens very rarely, is a little like what happens to you or with your thinking; 3 - It happens on a regular basis, or is very similar to what happens to you or with your thinking; 4 - It always happens, very often, or it is exactly what happens to you or with your thinking. '' After pilot testing, and based on the estimate of the population average, the sample of at least 320 women was established. Data collection occurred in the Health Care Units of São José dos Pinhais, Paraná, Brazil, during the waiting interval for care, in a room reserved for this purpose. At the time, the county was divided into five health districts, and the number of women interviewed in each Regional Health District was proportional to the size of the resident population in the area. The inclusion criteria were: 18 years or older, living in an affective relationship or having this experience at least once in their lives, having children, seeking the health service for any reason, agreeing to participate in the study, and signing the Terms of Free and Informed Consent.

Compilation of data and statistical validation

Data were tabulated in the Microsoft Excel® spreadsheet program for Windows, version 7, and transferred into the Statistical Package for Social Sciences (SPSS), version 22. Through exploratory analysis, omissions, extreme cases and distribution of variables were found. Removing the omitted and extreme cases, the sample was reduced from 323 to 321 women. Subsequently, the factor analysis (FA) was performed, identifying the separate dimensions of the structure and determining the extent to which each variable explained each dimension, thus achieving the two main uses of FA, abstract and data reduction. Factor analysis was used, as it assists with the selection of a representative subset of variables, or even the development of new variables to replace the original, retaining its original condition. In summary, FA is an interdependent technique in which all variables are considered simultaneously, each variable related to all others, even by employing the concept of the statistical variable, linear composition variables. In FA, the statistical variables (factors) are formed to maximize the power of the whole explanation.15 The internal consistency was verified using the Kaiser-Meyer-Olkin (KMO) analysis.

Preparation of the final instrument

After statistical analysis, 25 phrases were confirmed, corresponding to 15 indicators of gender subordination in the family, able to capture the vulnerability to gender violence within the family environment.

RESULTS

The data relating to the identification of clients showed a mean age of 39 years old, married or living with a partner in a stable union, Christian beliefs, a mean of two children, elementary school education, working in activities related to care of the homes or business premises, as housekeepers, daily workers, maids, general service assistants, or worked in the commercial sector (shop assistants, cashiers, saleswomen), although a large part did not have remunerated activity. Most (57.9%) recognized suffering some kind of physical or psychological violence, at least once in their lifetime, and most mentioned the aggressors were their husbands or boyfriends (31.5%), ex-husbands or ex-boyfriends (24.1%), or others (8.0%).

Statistical validation

All instrument items showed a non-normal distribution (p>0.05), verified by means of the Kolmogorov-Smirnov and Shapiro-Wilke tests. However, component analysis is robust for this type of violation of assumption. The KMO analysis of 0.85 showed that the matrix had high factorability. The K1 analysis (eigenvalue equal to or greater than one) suggested the existence of up to nine components, yet the parallel analysis, calculated by the Monte Carlo PCA software, indicated the existence of, at the most, four components and the segmentation diagram indicated the presence of up to three components.

Principal Axis Factoring (PAF) analysis of the instrument was performed for extraction of two, three and four factors, to compare the results with Oblimin rotation, Kaiser normalization and exposure of factor loadings above 0.3. The analysis of internal consistency of items, for the extraction of both four factors as well as three factors, indicated that only the first two factors had a satisfactory Cronbach's alpha (values above 0.8). The Cronbach's alpha value demonstrates the internal consistency of the item. The closer the value is to 1, the higher the internal consistency of what is being evaluated.16. In Factor 1, phrases that reinforced the subordination remained (13 of 16), and they related to home maintenance and the family structure in the areas of household and external production, corresponding to the indicators: reconciling family and professional life; professional reorganization post-wedding or birth of children; power of decision over the household expenses, using personal time and expenses, children's education; responsibility for the family support, housekeeping and children. In Factor 2, phrases that gave the idea of overcoming subordination were grouped (seven of nine) and connected to the marital relationship: meaning of marriage, widowhood, infidelity, divorce and divorced person. Among the nine phrases that did not fit into either of the two factors, seven represented overcoming subordination. Five of the nine phrases that did not fit in either of the factors were related to the social network and family support (Table 2).

Based on these scores, the results of the factor scores were analyzed from the disaggregated instrument for responses from the Abuse Assessment Screen (AAS).14 Separating the respondent according to the answer to the first question of the AAS, ''Have you ever been emotionally or physically abused by your partner or someone important to you?'', the highest means were linked to the group that reported suffering violence at least once in life. In Factor 1, the group saying that it had never experienced violence was 1.70, while the mean of the group that reported having suffered violence, increased to 2.31. There was also a difference in the mean of Factor 2 (3.12 for the group that said no, and 3.45 for the group that answered yes), which is reflected in the mean of the general factor (2.72 for the group that answered yes; 2.22 for the group said no).

For the group of women who suffered physical abuse in the last twelve months, the mean of Factor 1 was higher (2.63 for those who answered yes, and 2.01 for those who answered no), but the mean for Factor 2 was lower (3.26 for the group that answered yes, and 3.32 for the group that said no). The sample was separated between those that answered yes or no to the question ''In the last year (12 months), did someone force you to have sexual activities or relations?'' In the group of women who answered yes, the mean for Factor 1 was 3.14, and for Factor 2 was 3.49, while for women who reported not having suffered sexual violence, the means for Factor 1 and Factor 2 were 2.03 and 3.31, respectively.

Grouping the respondents among those answered yes or no to the question: ''Are you afraid of your partner or someone listed above?'' (the list included the husband, ex-husband, boyfriend, stranger, others) the mean of factors 1 and 2 were 2.60 and 3.58, respectively, for those who answered yes and 1.94 and 3.26, respectively, for those that responded no. Considering that the mean values of Factor 1 - composed of phrases illustrating the daily situations that reinforce gender subordination in the family - were always higher for the group that answered yes - who had experienced some type of violence - it enables us to relate gender subordination to domestic violence against women.

In factor 2, composed of phrases referring to overcoming subordination, the mean of women who reported having experienced violence are also higher (with one exception, the group of those who had suffered aggression in the last twelve months). However, phrases included in Factor 2 were more subjective and described the opinion of women on certain issues (You cannot live for appearances...; Infidelity has no forgiveness ...; In widowhood when love was great we get sad...). Thus, by agreeing to these phrases, it is possible to understand that the respondents recognized that subordination needed to be defeated, but it had not yet happened.

The final product of the elaboration and validation process of the questionnaire for identifying vulnerability to domestic violence by gender subordination in the family is a tool of phrases separated in two groups: Group 1 - phrases that indicate gender subordination, and group 2 - items that demonstrate the overcoming of subordination (Table 3):

Although gender studies seek to expand and diversify the knowledge about the relationship between men and women, indicating how the process of social determination has resulted in inequality of power, research into databases did not show any study proving the relationship between gender subordination and the occurrence of domestic violence. The findings of this study show that women assumed roles that were previously regarded as masculine (I pay for all the household expenses, including his ...), but the reverse is not yet reciprocal (Even being unemployed, my husband does not take care of the kids for me to work). This reinforces that gender subordination is intrinsically linked to vulnerability to domestic violence and shows that women who suffer domestic violence, even while they recognized the need to break with the gender subordination, cannot.

Violence is not a personality trait related to the male or female sex, nor do genetic characteristics determine that men are more violent and women more fragile and submissive, and therefore, subordinate. What this study supports is that the violent, streak will conform with the gender construction, which in turn is linked to the way of living and surviving in each society and, the social implementation of gender has reserved a role of subordination for women, leaving them more vulnerable to domestic violence. The state has based its norms and interventions in healthcare, to maintain the workforce, reducing the health needs to what is expressed in terms of physical deterioration, at the biological level, which reinforces the non-awareness of the individuals to the determinants of the health-disease to which they are exposed.18 Health professionals need to develop techniques for approach beyond the care for injuries, to give appropriate responses to situations of gender violence. It is necessary to look at gender violence in the context of the collective plan, structured in an ethical-philosophical framework that seeks the critical interpretation of data, basing on the gender category and distancing the analysis of violence against women from those models that restrict individual responsibility to causality. Only then will the health practices will constitute strategies to facilitate awareness and empowerment of women, to rebuild relationships based on gender equality, overcoming subordination.17

Conclusion. The development and validation of a questionnaire for identifying vulnerability for domestic violence by gender subordination in the family showed that it is possible to identify women vulnerable to domestic violence through gender subordination indicators; however, there was no time to enable the multidisciplinary team to use the instrument.

More research is needed relating gender subordination to domestic violence against women. Further studies may explore the education of health workers, especially the nurses, for using this questionnaire in primary care services, to check whether the use of the instrument is useful for the planning of individual or collective interventions.